Discovery | |
---|---|
Discovery site | Kepler Space Observatory |
Discovery date | 2014 |
Transit | |
Orbital characteristics | |
~0.209 AU | |
Eccentricity | null[1] |
33.006[1] d | |
Inclination | null[1] |
Star | Kepler-277 |
Physical characteristics | |
3.36 +0.83 −0.72[1] R🜨 | |
Mass | 64.2 +18.1 −15.7[1][2] ME |
Mean density | 9.33+15.33 −5.69 g cm−3 |
5.69+6.12 −2.93 g | |
Temperature | 745 K (472 °C; 881 °F)[3] |
Kepler-277c (also known by its Kepler Objects of Interest designation KOI-1215.02) is the third most massive and second-largest rocky planet ever discovered, with a mass about 64 times that of Earth. Discovered in 2014 by the Kepler Space Telescope, Kepler-277c is a Neptune-sized exoplanet with a very high mass and density for an object of its radius, suggesting a composition made mainly of rock with some amounts of water. Along with its sister planet, Kepler-277b, the planet's mass was determined using transit-timing variations (TTVs).